1. Field of the Invention
The present invention generally relates to a motorcycle or scooter comprising an engine suspended from a main frame member that extends rearward from a steering head pipe.
2. Description of the Related Art
Motorcycles and scooters mainly used for commuting or business purpose generally comprise a backbone type frame. The frame comprises a steering head pipe that supports a front fork. The frame also comprises a main frame member that extends rearward from the steering head pipe.
In such vehicles, the main frame member typically forms the primary frame structure. Brackets can be provided along an intermediate portion of the main frame member and the engine can be suspended from those brackets. As can be imagined, the brackets generally protrude downward from the main frame member. As such, the lower edges of the brackets extend longitudinally along a top face of the crankcase. As example of such a construction is shown in JP-A-2001-3723, in which the front ends and the rear ends of the brackets are connected to the crankcase.
As shown, a space is defined between the top face of the crankcase and the main frame member and this space is generally the same as the height of the brackets. When the motorcycle is viewed from the side, this space is generally enclosed by the brackets. Accordingly, if an auxiliary component for the engine, such as a start motor, were to be positioned on the crankcase of the engine in the proximity of the brackets, the brackets would necessarily be displaced upward by an amount corresponding to the volume or vertical dimension of the auxiliary component. The upward displacement results in an increase in distance between the crankcase and the main frame member.
The vertical position of the engine above the road surface is normally determined by, for example, a tradeoff with the angle of a road banking over which the vehicle can be ridden without causing the engine to bottom on the road surface. Thus, in order to maintain the engine at a desired distance from the ground, the spacing between the ground and the main frame member tends to be enlarged because the position of the main frame member is largely determined based on the vertical position of the engine. The seat is mounted to the main frame member. Therefore, because the spacing between the ground and the main frame member is fairly large, the seat is even further spaced from the ground. The seat, then, is positioned fairly high on the vehicle, which makes it difficult for a rider to put both feet on the ground easily.